NXP Semiconductors
UM11079
IoT Module base board
UM11079_OM40006.docm
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2017, 2018. All rights reserved.
User manual
Rev. 1.0
— March 20, 2018
14 of 23
connector P2 to the external target (it is recommended that power is removed while
making these changes/connections). The Link2 can then be used in the same way (using
CMSIS-DAP or J-link firmware with any supported IDE, or using DFU boot if using
MCUXpresso IDE) as described earlier in this section.
5. Board power connections & measurement
The OM40006 board re5V input to power the on-board voltage regulators which
in turn power the Link2 debug probe and other +3.3V circuits, the installed module and
and the A5V and +3.3V power rails. When the main external power source is
from the Link2 side USB micro B-type connector (J7), both the Link side and Module
sections of the board are powered. When the main external power is from the power
only USB micro B-type connector (J1), or one of more of the USB device ports (USB0 or
USB1), only the Module and supporting devices and peripherals are powered.
5.1.1 Module Vsense resistor current measurement
The voltage across a pair of 1
Ω resistors in series with the target Module VDD can be
manually measured at JP5 across pins 1 and 4 on the PCB. For a higher range of current
a jumper should be installed between pins 3 and 4 of JP5 to short out one of these
resistors. The voltmeter positive probe is applied to JP5 pin 1 (see silkscreen labelling)
and pin 4
. Use Ohm’s law to calculate the current (Module current = measured voltage /
2Ω). As an example if the measured voltage is 20mV, then 20e-3 / 2Ω = 10mA.
5.1.2 Module VDD current measurement using a current meter
A current meter may be inserted at JP5 between pins 5 and 6 to measure the Module
VDD input current. Note that a jumper needs to be installed in the 5-6 position when an
ammeter is not present so power can reach the Module.
6. Board peripheral connections
6.1 USART ports and VCOM support
The OM40006 board provides access to USART connections from the installed module
J4 connector pins 93 and 97 to the Link2 debug probe or external UART connector P4.
When using P4, install jumper JP7 to prevent contention with the Link2 probe.
The factory default CMSIS-DAP Link2 image and optional J-Link image include UART
bridge functionality (VCOM support); this firmware can be programmed using the
LPCScrypt utility, available at http://www.nxp.com/lpcutilities.
The P4 header is designed to be used with an external serial to USB or other 3.3V serial
device. Note that the connections at P4 are made directly to the Module, so care should
be taken to avoid ESD discharge and voltages outside the ratings of the device I/O pins.
Table 3.
P4 connections
Pin
Function
1
Ground
2
RXD (from Module)
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from